/*
 * Copyright (c) MuleSoft, Inc.  All rights reserved.  http://www.mulesoft.com
 * The software in this package is published under the terms of the CPAL v1.0
 * license, a copy of which has been included with this distribution in the
 * LICENSE.txt file.
 */

package org.mule.runtime.core.streaming;

import static org.mule.test.allure.AllureConstants.StreamingFeature.STREAMING;

import org.mule.runtime.core.internal.streaming.object.iterator.QueueProducer;
import org.mule.tck.size.SmallTest;
import org.mule.runtime.core.api.util.queue.Queue;

import java.io.Serializable;
import java.util.HashSet;
import java.util.Iterator;
import java.util.Set;

import junit.framework.Assert;

import org.junit.Before;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.mockito.Mock;
import org.mockito.Mockito;
import org.mockito.invocation.InvocationOnMock;
import org.mockito.runners.MockitoJUnitRunner;
import org.mockito.stubbing.Answer;
import io.qameta.allure.Feature;

@SmallTest
@RunWith(MockitoJUnitRunner.class)
@Feature(STREAMING)
public class QueueProducerTestCase {

  @Mock
  private Queue queue;;

  private Set<String> values;
  private Iterator<String> valuesIterator;
  private QueueProducer<Serializable> producer;

  @Before
  public void setUp() throws Exception {
    this.values = new HashSet<String>();
    this.values.add("banana");
    this.values.add("chocolate");
    this.values.add("coke");

    this.valuesIterator = this.values.iterator();

    Mockito.when(this.queue.poll(Mockito.anyLong())).thenAnswer(new Answer<Serializable>() {

      @Override
      public Serializable answer(InvocationOnMock invocation) throws Throwable {
        return valuesIterator.hasNext() ? valuesIterator.next() : null;
      }
    });

    Mockito.when(this.queue.size()).thenReturn(this.values.size());

    this.producer = new QueueProducer<Serializable>(this.queue);
  }

  @Test
  public void happyPath() throws Exception {
    Set<Serializable> returnedValues = new HashSet<Serializable>();

    Serializable page = this.producer.produce();
    while (page != null) {
      returnedValues.add(page);
      page = this.producer.produce();
    }

    Assert.assertEquals(returnedValues.size(), this.values.size());

    for (String value : this.values) {
      Assert.assertTrue(returnedValues.contains(value));
    }

    Assert.assertNull(this.producer.produce());
  }

  @Test
  public void size() throws Exception {
    Assert.assertEquals(this.values.size(), this.producer.getSize());
  }

  @Test
  public void earlyClose() throws Exception {
    this.producer.produce();
    this.producer.close();

    Assert.assertNull(this.producer.produce());
  }

}
